package com.example.springboot.utils;

import cn.hutool.core.date.DateUtil;
import cn.hutool.core.util.StrUtil;
import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;
import com.example.springboot.entity.User;
import com.example.springboot.mapper.UserMapper;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import java.util.Date;

/**
 * 功能:
 * 作者: sdj
 * 日期: 2024/12/15 22:58
 */
@Component
public class TokenUtils {
    private static UserMapper staticUserMapper;

    @Resource
    private  UserMapper userMapper;

    @PostConstruct
    public void setUserService(){
        staticUserMapper=userMapper;
    }

    /**
     * 生成token
     *
     * @return token
     */
    public static String createToken(String userId,String sign){
        return JWT.create().withAudience(userId) //将userId保存到token里面，作为载荷
                .withExpiresAt(DateUtil.offsetHour(new Date(),2))  //2时候后token过期
                .sign(Algorithm.HMAC256(sign)); //以password作为token的密钥
    }

    /**
     * 获取当前登录用户信息
     *
     * @return user对象
     */
    public static User getCurrentUser(){
       try {
           HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest();
           String token = request.getHeader("token");
           if (StrUtil.isNotBlank(token)){
               String userId = com.auth0.jwt.JWT.decode(token).getAudience().get(0);
               return staticUserMapper.selectById(Integer.valueOf(userId));
           }
       }catch (Exception e){
           return null;
       }
       return null;
    }
}
